[Bug tree-optimization/108582] New: ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[Bug tree-optimization/108582] New: ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

            Bug ID: 108582
           Summary: ICE on valid code at -Os and above with "-fno-tree-ccp
                    -fno-tree-dce": tree check: expected class ‘type’,
                    have ‘exceptional’ (error_mark) in
                    useless_type_conversion_p, at gimple-expr.cc:87
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhendong.su at inf dot ethz.ch
  Target Milestone: ---

It appears to be a recent regression from 12.2. 

Compiler Explorer: https://godbolt.org/z/91oGh1W8K


[617] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/13.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror
--disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.1 20230128 (experimental) [master r12-4647-g3f861a5c8fd] (GCC)
[618] %
[618] % gcctk -O3 small.c; ./a.out
[619] %
[619] % gcctk -O3 -fno-tree-ccp -fno-tree-dce small.c
during GIMPLE pass: phiopt
small.c: In function ‘main’:
small.c:3:5: internal compiler error: tree check: expected class ‘type’, have
‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87
    3 | int main() {
      |     ^~~~
0x6e9981 tree_class_check_failed(tree_node const*, tree_code_class, char
const*, int, char const*)
        ../../gcc-trunk/gcc/tree.cc:8959
0xbad6e3 tree_class_check(tree_node*, tree_code_class, char const*, int, char
const*)
        ../../gcc-trunk/gcc/tree.h:3653
0xbad6e3 useless_type_conversion_p(tree_node*, tree_node*)
        ../../gcc-trunk/gcc/gimple-expr.cc:87
0xfb106c verify_gimple_assign_binary
        ../../gcc-trunk/gcc/tree-cfg.cc:4292
0xfc1897 verify_gimple_assign
        ../../gcc-trunk/gcc/tree-cfg.cc:4829
0xfc1897 verify_gimple_stmt
        ../../gcc-trunk/gcc/tree-cfg.cc:5088
0xfc9448 verify_gimple_in_cfg(function*, bool, bool)
        ../../gcc-trunk/gcc/tree-cfg.cc:5583
0xe5a333 execute_function_todo
        ../../gcc-trunk/gcc/passes.cc:2091
0xe5adb2 execute_todo
        ../../gcc-trunk/gcc/passes.cc:2145
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
[620] %
[620] % cat small.c
int a, c, d, e, f;
char b;
int main() {
  int g = 1;
  char h[1] = {0};
  while (a) {
    if (f) {
      b = 0;
      if (d)
        continue;
    }
    if (a < 1) {
      g = 0;
      goto L;
    }
  }
  while (c) {
    char *j = h;
    int k;
  L:
    if (e && !g)
      k |= 2 | (*j < 0);
  }
  return 0;
}

[Bug tree-optimization/108582] [13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|unknown                     |13.0
     Ever confirmed|0                           |1
            Summary|ICE on valid code at -Os    |[13 Regression] ICE on
                   |and above with              |valid code at -Os and above
                   |"-fno-tree-ccp              |with "-fno-tree-ccp
                   |-fno-tree-dce": tree check: |-fno-tree-dce": tree check:
                   |expected class ‘type’, have |expected class ‘type’, have
                   |‘exceptional’ (error_mark)  |‘exceptional’ (error_mark)
                   |in                          |in
                   |useless_type_conversion_p,  |useless_type_conversion_p,
                   |at gimple-expr.cc:87        |at gimple-expr.cc:87
             Status|UNCONFIRMED                 |NEW
           Keywords|                            |ice-on-valid-code
   Target Milestone|---                         |13.0
   Last reconfirmed|                            |2023-01-28

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
#5  0x000000000162e9cc in verify_gimple_assign (stmt=0x7ffff741c2c0) at
/home/apinski/src/upstream-gcc/gcc/gcc/tree-cfg.cc:4829
4829          return verify_gimple_assign_binary (stmt);
(gdb) p debug_gimple_stmt(stmt)
_4 = _13 & _28;

#4  0x000000000162c6b7 in verify_gimple_assign_binary (stmt=0x7ffff741c2c0) at
/home/apinski/src/upstream-gcc/gcc/gcc/tree-cfg.cc:4292
4292      if (!useless_type_conversion_p (lhs_type, rhs1_type)
(gdb) p debug_generic_expr(lhs_type)
int
$2 = void
(gdb) p debug_generic_expr(rhs1_type)
<<< error >>>
$3 = void

[Bug tree-optimization/108582] [13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot gnu.org

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Mine I think ...

[Bug tree-optimization/108582] [13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
PHI g_9 reduced for COND_EXPR in block 7 to g_8.
statement un-sinked:
k_22 = k_11 | iftmp.5_13;
Removing basic block 8
;; basic block 8, loop depth 0
;;  pred:       7
# iftmp.5_13 = PHI <2(7)>
;;  succ:       9

Looks like match-and-simplify phiopt does not take into account PHInodes ...

[Bug tree-optimization/108582] [13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This should fix the issue:
apinski@xeond:~/src/upstream-gcc/gcc/gcc$ git diff tree-ssa-phiopt.cc
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index c3a889dc593..a7ab6ce4ad9 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -1002,6 +1002,11 @@ match_simplify_replacement (basic_block cond_bb,
basic_block middle_bb,
       if (!single_pred_p (middle_bb))
        return false;

+      /* The middle bb cannot have phi nodes as we don't
+        move those assignments yet. */
+      if (!gimple_seq_empty_p (phi_nodes (middle_bb)))
+       return false;
+
       stmt_to_move = last_and_only_stmt (middle_bb);
       if (!stmt_to_move)
        return false;

[Bug tree-optimization/108582] [12/13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
   Target Milestone|13.0                        |12.3
            Summary|[13 Regression] ICE on      |[12/13 Regression] ICE on
                   |valid code at -Os and above |valid code at -Os and above
                   |with "-fno-tree-ccp         |with "-fno-tree-ccp
                   |-fno-tree-dce": tree check: |-fno-tree-dce": tree check:
                   |expected class ‘type’, have |expected class ‘type’, have
                   |‘exceptional’ (error_mark)  |‘exceptional’ (error_mark)
                   |in                          |in
                   |useless_type_conversion_p,  |useless_type_conversion_p,
                   |at gimple-expr.cc:87        |at gimple-expr.cc:87

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note this is a latent bug since it was introduced by r12-1309-gc4574d23cb0734 .
I don't know what changed that cause the IR to be different on the trunk but I
just know it is a latent bug.

[Bug tree-optimization/108582] [12/13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Patch submitted:
https://gcc.gnu.org/pipermail/gcc-patches/2023-January/610817.html

[Bug tree-optimization/108582] [12/13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug tree-optimization/108582] [12/13 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>:

https://gcc.gnu.org/g:876b3e0514bc8cb2256c44db56255403bedfa52d

commit r13-5493-g876b3e0514bc8cb2256c44db56255403bedfa52d
Author: Andrew Pinski <apinski@marvell.com>
Date:   Sat Jan 28 18:27:08 2023 +0000

    Fix PR 108582: ICE due to PHI-OPT removing a still in use ssa_name.

    This patch adds a check in match_simplify_replacement to make sure the
middlebb
    does not have any phi-nodes as we don't currently move those.
    This was just a thinko from before.

    Ok? Bootstrapped and tested on x86_64-linux-gnu with no regressions?

            PR tree-optimization/108582

    gcc/ChangeLog:

            * tree-ssa-phiopt.cc (match_simplify_replacement): Add check
            for middlebb to have no phi nodes.

    gcc/testsuite/ChangeLog:

            * gcc.dg/pr108582-1.c: New test.

[Bug tree-optimization/108582] [12 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |11.1.0, 13.0
      Known to fail|                            |12.2.0
            Summary|[12/13 Regression] ICE on   |[12 Regression] ICE on
                   |valid code at -Os and above |valid code at -Os and above
                   |with "-fno-tree-ccp         |with "-fno-tree-ccp
                   |-fno-tree-dce": tree check: |-fno-tree-dce": tree check:
                   |expected class ‘type’, have |expected class ‘type’, have
                   |‘exceptional’ (error_mark)  |‘exceptional’ (error_mark)
                   |in                          |in
                   |useless_type_conversion_p,  |useless_type_conversion_p,
                   |at gimple-expr.cc:87        |at gimple-expr.cc:87

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed on the trunk, still latent in GCC 12, will be backporting the patch next
week.

[Bug tree-optimization/108582] [12 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Andrew Pinski
<pinskia@gcc.gnu.org>:

https://gcc.gnu.org/g:6f23c9077feebb29c2a28ffe89b287286df27d6d

commit r12-9114-g6f23c9077feebb29c2a28ffe89b287286df27d6d
Author: Andrew Pinski <apinski@marvell.com>
Date:   Sat Jan 28 18:27:08 2023 +0000

    Fix PR 108582: ICE due to PHI-OPT removing a still in use ssa_name.

    This patch adds a check in match_simplify_replacement to make sure the
middlebb
    does not have any phi-nodes as we don't currently move those.
    This was just a thinko from before.

    Committed on the GCC 12 branch after a bootstrap/test on x86_64-linux-gnu.

            PR tree-optimization/108582

    gcc/ChangeLog:

            * tree-ssa-phiopt.cc (match_simplify_replacement): Add check
            for middlebb to have no phi nodes.

    gcc/testsuite/ChangeLog:

            * gcc.dg/pr108582-1.c: New test.

    (cherry picked from commit 876b3e0514bc8cb2256c44db56255403bedfa52d)

[Bug tree-optimization/108582] [12 Regression] ICE on valid code at -Os and above with "-fno-tree-ccp -fno-tree-dce": tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108582

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #10 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed.